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In this study, tocopherol‐derived ionizable lipids were synthesized to create functional lipid nanoparticles for mRNA delivery. Tocopherol succinate is considered a biocompatible material because it has anti‐cancer effects and degrades into vitamin E in the body. Two types of new ionizable tocopherol derivative lipids (DMT and AIT) were synthesized by introducing ionizable functional groups. The synthesized tocopherol lipids were used to make lipid nanoparticles with helper lipid, cholesterol, and PEG‐DMG. The DMT LNP showed high mRNA encapsulation efficiency. Using HeLa cell lines, it was confirmed that gene transfection efficiency was increased approximately 2‐fold in DMT LNP‐treated cells compared to that of MC3 LNP. The two types of tocopherol derivative lipids exhibited high cell viability of over 90%, confirming very low levels of toxicity. The results of this study confirmed that lipid nanoparticles using newly developed ionizable tocopherol derivatives have potential as biocompatible and effective mRNA delivery vehicles. [ABSTRACT FROM AUTHOR]

Background: This study examines the feasibility and effects of introducing microRNA mimic into red blood cells (RBCs) at the initial phases of Plasmodium falciparum 3D7 (Pf3D7) infection. The aim is to determine the correlation between increased expression of miR-451a and parasitaemia. Methods: In this study miR-mimic-451a labelled with Cy3 and transfected into control and infected RBCs using lipofectamine and analysed using the fluorescence microscopy and flow cytometry. The study demonstrated the efficacy of miR-451a by treating pre-and post-transfected control RBCs and Pf3D7-infected RBCs with miR-mimic-451a. We also examined its impact on % growth inhibition of Pf3D7, oxidative stress markers (Luminometry, LPO, SOD, CAT, GSH and GPx). Additionally, determination of pH, haemoglobin (Hb), and proteomic profile performed using SDS-PAGE. Results: Modified expression level of mir-451a has the potential to change the progression of the infection and yielded a 50% decrease in parasitaemia within 48 h. Moreover, transfected samples were shown to be efficacious in counteracting the oxidative stress-induced alterations during Pf3D7 infection and enable to return the cells towards the normalcy. Modified proteomic profile of transfected iRBCs demonstrates the correlation between overexpression of miRNA and protein expression. where, the major changes were observed in the heavy molecular weight proteins more than 57 kDa. Conclusion: The study reveals promising effects of miR-mimic-451a enrichment during RBC stages of Pf3D7, offering insights into potential malaria therapeutic strategies and potential biomedical research implications. [ABSTRACT FROM AUTHOR]

The invasive ascomycete Hymenoscyphus fraxineus is the causative agent for ash dieback on the European species Fraxinus excelsior and Fraxinus angustifolia, and there is concern that it is going to replace the native, closely related and nonpathogenic Hymenoscyphus albidus. Fungal management in forests is limited, and alternative approaches for control are needed. Within the scope of the project "FraxForFuture", several strategies are being investigated. One idea comprises the use of a viral hyperparasite, which can induce a reduced virulence in the fungal host H. fraxineus in an antagonist-like system. This phenomenon, the reduction of fungal virulence by a viral infection, is known as hypovirulence, and a similar method has already been established to control the Chestnut Blight in Europe. We examined 34 isolates of H. fraxineus for both their virulence and presence of a viral infection. Although a predominant number of isolates were found to be infected with Hymenoscyphus mitovirus 1 (HfMV1), no additional viruses were detected, and our data did not indicate a link to reduced virulence. The search for a viral infection was extended to one isolate of H. albidus in which we found and characterized a novel mycovirus. Based on phylogenetic analysis and sequence properties, it was assigned to the genus Victorivirus in the family of Totiviridae and was tentatively denominated as Hymenoscyphus albidus victorivirus 1. This novel and native mycovirus might be suitable for inducing hypovirulence in H. fraxineus as a biocide. [ABSTRACT FROM AUTHOR]

Lipid nanoparticles (LNPs) are currently the most commonly used non-viral gene delivery system. Their physiochemical attributes, encompassing size, charge and surface modifications, significantly affect their behaviors both in vivo and in vitro. Nevertheless, the effects of these properties on the transfection and distribution of LNPs after intramuscular injection remain elusive. In this study, LNPs with varying sizes, lipid-based charges and PEGylated lipids were formulated to study their transfection and in vivo distribution. Luciferase mRNA (mLuc) was entraped in LNPs as a model nucleic acid molecule. Results indicated that smaller-sized LNPs and those with neutral potential presented superior transfection efficiency after intramuscular injection. Surprisingly, the sizes and charges did not exert a notable influence on the in vivo distribution of the LNPs. Furthermore, PEGylated lipids with shorter acyl chains contributed to enhanced transfection efficiency due to their superior cellular uptake and lysosomal escape capabilities. Notably, the mechanisms underlying cellular uptake differed among LNPs containing various types of PEGylated lipids, which was primarily attributed to the length of their acyl chain. Together, these insights underscore the pivotal role of nanoparticle characteristics and PEGylated lipids in the intramuscular route. This study not only fills crucial knowledge gaps but also provides significant directions for the effective delivery of mRNA via LNPs. [ABSTRACT FROM AUTHOR]

Cancer poses a significant health challenge, with traditional treatments like surgery, radiotherapy, and chemotherapy often lacking in cell specificity and long‐term curative potential. Chimeric antigen receptor T cell (CAR‐T) therapy,utilizing genetically engineered T cells to target cancer cells, is a promising alternative. However, its high cost limits widespread application. CAR‐T manufacturing process encompasses three stages: cell isolation and activation, transfection, and expansion.While the first and last stages have straightforward, commercially available automation technologies, the transfection stage lags behind. Current automated transfection relies on viral vectors or bulk electroporation, which have drawbacks such as limited cargo capacity and significant cell disturbance. Conversely, micro and nano‐tool methods offer higher throughput and cargo flexibility, yet their automation remains underexplored.In this perspective, the progress in micro and nano‐engineering tools for CAR‐T transfection followed by a discussion to automate them is described. It is anticipated that this work can inspire the community working on micro and nano transfection techniques to examine how their protocols can be automated to align with the growing interest in automating CAR‐T manufacturing. [ABSTRACT FROM AUTHOR]

We describe in this work an evaluation of bundles of hollow mesoporous silicon nanotubes to facilitate transfection of HeLa cells using small interfering RNA designed to knock down expression of Enhanced Green Fluorescent Protein (eGFP). These experiments entail direct visualization of the nanotube bundles associated with the cells using both scanning electron microscopy (SEM) and confocal fluorescence imaging. These nanotube bundles are generated by surface modification of nanotube arrays with aminopropyl‐triethoxysilane (APTES), followed by their ultrasonication in water, to create the amine‐terminated structures capable of electrostatic conjugation of siRNA at an efficiency of 23%–50% (depending on initial siRNA concentration). Delivery and transfection to HeLa cells are verified by quantification of fluorescence imaging; an average percent knockdown of ∼50% eGFP is achieved. As nanoscale drug delivery vehicles are expected to be resorbed in clinical use, we also assess SiNT bundle degradation during the above in vitro timescale using scanning and transmission electron (TEM) microscopies. We conclude with a brief discussion of challenges and opportunities in future experiments involving this platform. [ABSTRACT FROM AUTHOR]

Short interfering RNA (siRNA) therapeutics have soared in popularity due to their highly selective and potent targeting of faulty genes, providing a non‐palliative approach to address diseases. Despite their potential, effective transfection of siRNA into cells requires the assistance of an accompanying vector. Vectors constructed from non‐viral materials, while offering safer and non‐cytotoxic profiles, often grapple with lackluster loading and delivery efficiencies, necessitating substantial milligram quantities of expensive siRNA to confer the desired downstream effects. We detail the recombinant synthesis of a diverse series of coiled‐coil supercharged protein (CSP) biomaterials systematically designed to investigate the impact of two arginine point mutations (Q39R and N61R) and decahistidine tags on liposomal siRNA delivery. The most efficacious variant, N8, exhibits a twofold increase in its affinity to siRNA and achieves a twofold enhancement in transfection activity with minimal cytotoxicity in vitro. Subsequent analysis unveils the destabilizing effect of the Q39R and N61R supercharging mutations and the incorporation of C‐terminal decahistidine tags on α‐helical secondary structure. Cross‐correlational regression analyses reveal that the amount of helical character in these mutants is key in N8's enhanced siRNA complexation and downstream delivery efficiency. [ABSTRACT FROM AUTHOR]

Abstract Lipid nanoparticles (LNPs) are currently the most commonly used non-viral gene delivery system. Their physiochemical attributes, encompassing size, charge and surface modifications, significantly affect their behaviors both in vivo and in vitro. Nevertheless, the effects of these properties on the transfection and distribution of LNPs after intramuscular injection remain elusive. In this study, LNPs with varying sizes, lipid-based charges and PEGylated lipids were formulated to study their transfection and in vivo distribution. Luciferase mRNA (mLuc) was entraped in LNPs as a model nucleic acid molecule. Results indicated that smaller-sized LNPs and those with neutral potential presented superior transfection efficiency after intramuscular injection. Surprisingly, the sizes and charges did not exert a notable influence on the in vivo distribution of the LNPs. Furthermore, PEGylated lipids with shorter acyl chains contributed to enhanced transfection efficiency due to their superior cellular uptake and lysosomal escape capabilities. Notably, the mechanisms underlying cellular uptake differed among LNPs containing various types of PEGylated lipids, which was primarily attributed to the length of their acyl chain. Together, these insights underscore the pivotal role of nanoparticle characteristics and PEGylated lipids in the intramuscular route. This study not only fills crucial knowledge gaps but also provides significant directions for the effective delivery of mRNA via LNPs. Graphical Abstract

CRISPR/Cas9-based genome engineering has revolutionized our ability to manipulate biological systems, particularly in higher organisms. Here, we designed a set of homology-directed repair donor templates that enable efficient tagging of endogenous proteins with affinity tags by transient transfection and selection of genome-edited cells in various human cell lines. Combined with technological advancements in single-particle cryogenic electron microscopy, this strategy allows efficient structural studies of endogenous proteins captured in their native cellular environment and during different cellular processes. We demonstrated this strategy by tagging six different human proteins in both HEK293T and Jurkat cells. Moreover, analysis of endogenous glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in HEK293T cells allowed us to follow its behavior spatially and temporally in response to prolonged oxidative stress, correlating the increased number of oxidation-induced inactive catalytic sites in GAPDH with its translocation from cytosol to nucleus.

Epitope tagging represents a powerful strategy for expedited identification, isolation, and characterization of proteins in molecular biological studies, including protein–protein interactions. We aimed to improve the reproducibility of epitope-tagged protein expression and detection by developing a range of plasmids as positive controls. The pJoseph2 family of expression plasmids functions in diverse cellular environments and cell types to enable the evaluation of transfection efficiency and antibody staining for epitope detection. The expressed green fluorescent proteins harbor five unique epitope tags, and their efficient expression in Escherichia coli, Drosophila Schneider's line 2 cells, and human SKOV3 and HEK293T cells was demonstrated by fluorescence microscopy and western blotting. The pJoseph2 plasmids provide versatile and valuable positive controls for numerous experimental applications.

Objective(s): Gene therapy is a hopeful approach for treatment of a wide range of life threatening disease from infectious and inherited diseases to cancer. Multifunctional Envelope-type Nano Device (MEND) is a new carrier as non-viral genetic vector. Moreover, associating peptide structures with the nuclear localization signals (NLSs), which contains various functional groups enables them to condense DNA and specifically transfer genetic material to the nucleus.Materials and Methods: In this study, two forms of low molecular weight protamine (LMWP) were used for preparation of MEND carrier. The MEND carriers were then targeted with GE11 ligand to obtain T-MEND structure. The size distribution of the resulting nanoparticles, as well as their transfection efficiency and cytotoxicity, were investigated on the A549 cell line.Results: Results demonstrated that the size of polyplex carrier’s formulation by both peptides (VV45 and VV32) was below 200 nm and MEND formulations were between 200-300 nm. T-MEND formulations contained VV32 and VV45 peptides showed slightly higher transfection than similar MEND formulations. Also, MEND formulation showed increased transfection efficiency compared to similar PD complexes. The result of metabolic activity test showed that MEND lipopolyplex did not represent any remarkable cytotoxicity.Conclusion: It can be concluded that multifunctional carriers designed based on LMWP are considered as the safe carrier for gene delivery. Presence of protamine and targeted ligand in the nanoparticulate structure did not increase the risk of cytotoxicity of carriers. So, MEND and T-MEND lipoplexes showed low cytotoxicity and acceptable transfection efficiency at the level of PEI 25 kDa.

Objective To compare the three different methods for direct transfection of small exogenous nicotinamide adenine dinucleotide phosphate(NADPH) into cells by a non-metabolic pathway. Methods Three different transfection reagents (X-tremeGENETM HP DNA, LipofectamineTM RNAiMAX and LipofectamineTM 2000) were used to find the transfection efficiency of NADPH into human osteosarcoma cell line U2OS and mouse embryonic fibroblast cell line 3T3L1. Their effects on adipocyte differentiation were compared by Oil Red O staining. Results Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increased intracellular NADPH level(P＜0.001). With the increase of NADPH transfection concentration (10 μmol/L NADPH and 10 μL transfection reagent), the level of NADPH in cells increased in a dose-dependent manner. In addition, three transfection reagents were used to transfect NADPH in 3T3L1 preadipocytes. Only cells transfected with NADPH using X-tremeGENE HP DNA transfection reagent contained more lipids than control cells (P＜0.001). Conclusions Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increases the level of NADPH in cells.

The enormous therapeutic potential of selective ribonucleic acid (RNA) interference has recently been manifested by the approval of several small interfering RNA (siRNA)‐based drugs. However, the efficacy of siRNA delivery is still limited, and an extensive search for alternative and highly effective delivery approaches is ongoing. With this aim, three generations of non‐viral vectors based on modified nanodiamonds (NDs) have been gradually developed in the past decade. They show great promise due to the negligible toxicity of the ND core. Here, a robust methodological approach is presented to enable the evaluation of new vector nanomaterials. Using a new type of third‐generation ND vector coated with a copolymer with tunable charge density, variables such as colloidal stability, surface electrostatic properties, the molecular composition of the copolymer, and the mode of complexation with siRNA are optimized. Using an innovative data processing strategy, the results are related to biological potency, toxicity, and cell proliferation. Finally, the optimized composition of a coating copolymer consisting of a cationic component, 2‐dimethylaminoethyl methacrylate, and an electroneutral biocompatible component, N‐(2‐hydroxypropyl) methacrylamide, is evaluated. The optimized NDs vectors are colloidally and biologically stable siRNA delivery tools with broad potential for RNA interference‐based therapeutics. [ABSTRACT FROM AUTHOR]

Polydopamine‐based materials, notably Polydopamine‐polyethyleneimine (PDA‐PEI), have gained considerable interest for surface‐mediated transfection. However, the high laser power density required to achieve high transfection efficiency poses a significant challenge in preserving cell viability. An organic photosensitizer CRO32TMI was developed to improve the photothermal conversion capability of PDA‐PEI. The modified PDA‐PEI‐CRO32TMI exhibited remarkable photothermal and photostability properties upon NIR irradiation, enabling it to achieve better transfection efficiency at lower laser power density as compared to the traditional solution or lipid‐based transfection methods. [ABSTRACT FROM AUTHOR]

Objective(s): Gene therapy is a hopeful approach for treatment of a wide range of life threatening disease from infectious and inherited diseases to cancer. Multifunctional Envelope-type Nano Device (MEND) is a new carrier as non-viral genetic vector. Moreover, associating peptide structures with the nuclear localization signals (NLSs), which contains various functional groups enables them to condense DNA and specifically transfer genetic material to the nucleus. Materials and Methods: In this study, two forms of low molecular weight protamine (LMWP) were used for preparation of MEND carrier. The MEND carriers were then targeted with GE11 ligand to obtain T-MEND structure. The size distribution of the resulting nanoparticles, as well as their transfection efficiency and cytotoxicity, were investigated on the A549 cell line. Results: Results demonstrated that the size of polyplex carrier's formulation by both peptides (VV45 and VV32) was below 200 nm and MEND formulations were between 200-300 nm. T-MEND formulations contained VV32 and VV45 peptides showed slightly higher transfection than similar MEND formulations. Also, MEND formulation showed increased transfection efficiency compared to similar PD complexes. The result of metabolic activity test showed that MEND lipopolyplex did not represent any remarkable cytotoxicity. Conclusion: It can be concluded that multifunctional carriers designed based on LMWP are considered as the safe carrier for gene delivery. Presence of protamine and targeted ligand in the nanoparticulate structure did not increase the risk of cytotoxicity of carriers. So, MEND and T-MEND lipoplexes showed low cytotoxicity and acceptable transfection efficiency at the level of PEI 25 kDa. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem cells (iPSCs) represent a groundbreaking advancement in stem cell research, offering new avenues for regenerative therapy and disease modeling. This study explores the application of calcium phosphate (CaP) nanoparticles in gene transfer studies involving iPSCs. By meticulously analyzing the characteristics of CaP nanoparticles—such as mean particle size and zeta potential—using dynamic light scattering (DLS), the research provides insights into their potential application in iPSC-related research. In addition, in vitro assessments were conducted on L929 mouse fibroblast cells to evaluate the biocompatibility of CaP nanoparticles, further demonstrating their potential utility. The results from the MTT assay indicate no significant toxic effects across various concentrations (ranging from 5 to 25 µg/µL), highlighting their safety profile and supporting their use in iPSC-related studies. Additionally, the CaP nanoparticle group exhibited lower total oxidant levels, suggesting potential antioxidant properties or the ability to mitigate oxidative stress. This reduction in oxidant levels may contribute to maintaining cell health and normal cellular functions, complemented by higher total antioxidant levels observed in the CaP group. Moreover, increased levels of cyclin D1 in the CaP group indicate enhanced cellular activity in proliferation and division processes, particularly significant during the G1 phase of the cell cycle. In summary, calcium phosphate nanoparticles play a multifaceted role in iPSC-related research, showcasing antioxidant properties, supporting cell proliferation, and potentially enhancing cell survival by inhibiting apoptosis. This research underscores their efficacy as non-viral carriers for genetic studies and sheds light on their application in gene transfer experiments. Successful transfection of L929 cells with a selected plasmid encoding Oct4-Sox2-Klf4-Myc-GFP demonstrates the effectiveness of CaP nanoparticles in delivering genetic material into cells. With a transfection efficiency persisting at 85% (± 3.4%) over a 72-h observation period, coupled with significant expression levels of key genes OCT-4 and SSEA-4 detected via flow cytometry (88%), CaP nanoparticles emerge as a promising tool for facilitating cellular reprogramming. [ABSTRACT FROM AUTHOR]

The red fluorescent protein (rfp)-blasticidin deaminase (bsd) fusion gene was transfected into Babesia ovata by electroporation with the plasmid DNA and selected with 15 µg/mL of blasticidin S under the in vitro culture condition. The transfected parasite with episomal DNA was selected and cultured for further analysis based on the presence of the rfp-bsd fusion gene by PCR and expression of the fusion protein by immunofluorescence antibody test under fluorescence microscopy for 2 months after the transfection. The results are the first, to our knowledge, to demonstrate the expression and stability of the episomal rfp-bsd fusion gene under the control of actin promoter as a selectable marker for the transfection system in B. ovata. [ABSTRACT FROM AUTHOR]

Macrophages are unique immune cells attracting growing attention as a potential candidate for cell‐based therapy for infectious diseases and cancer. Strategies that can reprogramme or gene‐edit macrophages hold potential across a spectrum of acute and chronic conditions. Herein, lipid nanoparticles (LNPs) are developed containing the ionizable lipid SM‐102, helper lipid monoolein which is known for self‐assembly in aqueous solutions into the inverse cubic lyotropic liquid crystalline mesophase, and cholesterol as an mRNA nanocarrier. The immortalized alveolar macrophage cell line (MH‐S cells) is utilized to investigate how cholesterol concentration impacts on mRNA delivery which is further validated using primary mouse alveolar macrophages isolated from the bronchoalveolar compartment and human monocyte derived macrophages. By using high‐throughput synchrotron small angle X‐ray scattering (SAXS), an acidification‐induced non‐ordered to ordered internal nanostructure transition of the formulated LNPs is observed, following the transition sequence of inverse micellar to hexagonal to cubic mesophase in the pH range from 7 to 4. Cholesterol is identified as another crucial component for superior mRNA transfection in macrophages, contributing to nanostructure transition and protein corona variation. Successful ex vivo mRNA transfection is also achieved in primary macrophages, highlighting the prospectivity of reprogramming macrophages as a cell therapy for lung diseases. [ABSTRACT FROM AUTHOR]

In humans, Entamoeba histolytica is the main pathogen causing various amoebiases, while E. moshkovskii falls between being a pathogen and non-pathogen. The two species have similar behavior patterns but differ significantly in pathogenicity, with previous studies and clinical data indicating that E. moshkovskii has a low level of pathogenicity. Meaningfully, the biological characteristics of E. moshkovskii make it a potential model organism and a protein display platform for studying the functions of important Entamoeba proteins. Here, an Amoeba-pcDNA3.1 vector capable of overexpressing E. histolytica-sourced Igl-C protein was constructed and successfully transfected into E. moshkovskii. High levels of expression of the Igl-C, EGFP, and NeoR genes were identified in Igl-C-transfected trophozoites using qRT-PCR, and they were subsequently confirmed using immunoblotting. Transfection of Igl-C protein improved the adherence and phagocytosis of E. moshkovskii, demonstrating that E. histolytica Igl mediated amoebic adhesion. Moreover, as a manifestation of protein virulence, the ability of post-transfected trophozoites to induce inflammation in host macrophages was also enhanced. In conclusion, this study utilizing the characteristics of E. moshkovskii confirmed its potential to serve as a model organism. E. moshkovskii could replace E. histolytica as the target of gene editing, allowing more efficient study of amoebic pathogenicity. [ABSTRACT FROM AUTHOR]

The effective delivery of synthetic RNA into mononuclear phagocytes is a prerequisite for experimental research and therapeutic development. However, traditional methods are highly ineffective and toxic for these cells. Here, we aimed to optimize a transfection protocol for primary bone marrow–derived phagocytes, specifically dendritic cells and macrophages, using lipid nanoparticles generated by microfluidics. Our results show that a lipid mixture similar to that used in Moderna's COVID-19 messenger RNA vaccine outperforms the others tested. Improved messenger RNA transfection can be achieved by replacing uridine with methylpseudouridine but not methoxyuridine, which interferes with transfection. The addition of diphenyleneiodonium or apocynin can enhance transfection in a cell type–dependent manner without adverse effects, while apolipoprotein E provides no added value. These optimized transfection conditions can also be used for microRNA agonists and antagonists. In sum, this study offers a straightforward, highly efficient, reproducible, and nontoxic protocol to deliver RNA into different primary mononuclear phagocytes in culture. [ABSTRACT FROM AUTHOR]

Objective To compare the three different methods for direct transfection of small exogenous nicotinamide adenine dinucleotide phosphate (NADPH) into cells by a non-metabolic pathway. Methods Three different transfection reagents (X-tremeGENETM HP DNA, LipofectamineTM RNAiMAX and LipofectamineTM 2000) were used to find the transfection efficiency of NADPH into human osteosarcoma cell line U2OS and mouse embryonic fibroblast cell line 3T3L1. Their effects on adipocyte differentiation were compared by Oil Red O staining. Results Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increased intracellular NADPH level(P＜0.001). With the increase of NADPH transfection concentration (10 μmol/L NADPH and 10 μL transfection reagent), the level of NADPH in cells increased in a dose-dependent manner. In addition, three transfection reagents were used to transfect NADPH in 3T3L1 preadipocytes. Only cells transfected with NADPH using X-tremeGENE HP DNA transfection reagent contained more lipids than control cells (P＜0.001). Conclusions Transfection of NADPH with X-tremeGENE HP DNA transfection reagent effectively increases the level of NADPH in cells. [ABSTRACT FROM AUTHOR]

BLOC-one-related complex (BORC) is a multiprotein complex composed of eight subunits named BORCS1–8. BORC associates with the cytosolic face of lysosomes, where it sequentially recruits the small GTPase ARL8 and kinesin-1 and -3 microtubule motors to promote anterograde transport of lysosomes toward the peripheral cytoplasm in non-neuronal cells and the distal axon in neurons. The physiological and pathological importance of BORC in humans, however, remains to be determined. Here, we report the identification of compound heterozygous variants [missense c.85T>C (p.Ser29Pro) and frameshift c.71-75dupTGGCC (p.Asn26Trpfs*51)] and homozygous variants [missense c.196A>C (p.Thr66Pro) and c.124T>C (p.Ser42Pro)] in BORCS8 in five children with a severe early-infantile neurodegenerative disorder from three unrelated families. The children exhibit global developmental delay, severe-to-profound intellectual disability, hypotonia, limb spasticity, muscle wasting, dysmorphic facies, optic atrophy, leuko-axonopathy with hypomyelination, and neurodegenerative features with prevalent supratentorial involvement. Cellular studies using a heterologous transfection system show that the BORCS8 missense variants p.Ser29Pro, p.Ser42Pro and p.Thr66Pro are expressed at normal levels but exhibit reduced assembly with other BORC subunits and reduced ability to drive lysosome distribution toward the cell periphery. The BORCS8 frameshift variant p.Asn26Trpfs*51, on the other hand, is expressed at lower levels and is completely incapable of assembling with other BORC subunits and promoting lysosome distribution toward the cell periphery. Therefore, all the BORCS8 variants are partial or total loss-of-function alleles and are thus likely pathogenic. Knockout of the orthologous borcs8 in zebrafish causes decreased brain and eye size, neuromuscular anomalies and impaired locomotion, recapitulating some of the key traits of the human disease. These findings thus identify BORCS8 as a novel genetic locus for an early-infantile neurodegenerative disorder and highlight the critical importance of BORC and lysosome dynamics for the development and function of the central nervous system. [ABSTRACT FROM AUTHOR]

In this investigation, low molecular weight polyethyleneimine (LMW PEI; 1.8 kDa branched PEI) was conjugated to phathalated dextrin. The aim of this chemical modification was to decorate PEI molecules with a hydrophilic layer to improve its biophysical properties while the phthalic moiety may improve the hydrophilic‐hydrophobic balance of the final structure. The polymers were prepared at various conjugation degrees ranging from 6.5% to 16.5% and characterized in terms of biophysical characteristics as well as their gene transfer ability and cell‐induced toxicity. The results showed that dextrin‐phthalated‐PEI (DPHPEI) polymer was able to form nanoparticles with the size range of around 118–170 nm, with the zeta potential of 6.2–9.5 mV. DPHPEI polymers could increase the level of desired protein expression in the cells by up to three folds compared with unmodified LMW PEI while the cell viability of the modified polymers was around 80%. The result of this study shows a promising approach to improve the transfection efficiency of LMW PEI while maintaining its low toxic effects. [ABSTRACT FROM AUTHOR]

Recombinant adeno‐associated viral vectors (rAAVs) are one of the most used vehicles for gene therapy, with five rAAV therapeutics commercially approved by the FDA. To improve product yield, we optimized the suspension production process of rAAV8 vectors carrying a proprietary transgene using a commercially available transfection reagent, FectoVIR‐AAV. Using a miniaturized automated 250 mL scale bioreactor system, we generated models of vector genome (vg) titer, capsid (cp) titer, and Vg:Cp percentage from two multivariate design of experiment studies, one centered around bioreactor operating parameters, and another based on the transfection conditions. Using the optimized process returned from these models, the vector genome titer from the bioreactor was improved to beyond 1 × 1012 vg/mL. Five critical parameters were identified that had large effects on the pre‐purification vector quantity—the transfection pH, production pH, complexation time, viable cell density at transfection, and transfection reagent to DNA ratio. The optimized process was further assessed for its performance extending to six AAV serotypes, namely AAV1, AAV2, AAV5, AAV6, AAV8, and AAV9 carrying a transgene encoding for green fluorescent protein (GFP). Five of the six serotypes returned higher vector genome titers than the control condition. These data suggest that the choice of transfection reagent is a major factor in improving vector yield. The multivariate design of experiment approach is a powerful way to optimize production processes, and the optimized process from one AAV vector can to some extent be generalized to other serotypes and transgenes to accelerate development timelines of new programs. [ABSTRACT FROM AUTHOR]

ABSTRACT Within the eukaryotic cell, the actin cytoskeleton is a crucial structural framework that maintains cellular form, regulates cell movement and division, and facilitates the internal transportation of proteins and organelles. External cues induce alterations in the actin cytoskeleton primarily through the activation of Rho GTPases, which then bind to a diverse array of effector proteins to promote the local assembly or disassembly of actin. We have harnessed the extensively studied functions of RhoA in the dynamics of the actin cytoskeleton to craft a practical series for Stage 2 Biology students. This series not only imparts essential tissue culture laboratory skills but also reinforces them through repetition. These activities are presented in a scenario designed for students to explore the function of a hypothetical RhoA family member. Students produce slides from transfected cells, undertake fluorescence microscopy, process the images using ImageJ, and compile their findings in a comprehensive scientific report. The composition of the report requires independent acquisition of new knowledge and synoptic learning. According to student feedback, this early experience greatly aids in solidifying and honing the skills required to report on more extensive and intricate research projects, such as capstone projects.

Expansion microscopy (ExM) is a promising technology that enables nanoscale imaging on conventional optical microscopes by physically magnifying the specimens. Here, we report the development of a strategy that enables i) on-demand labeling of subcellular organelles in live cells for ExM through transfection of fluorescent proteins that are well-retained during the expansion procedure; and ii) non-fluorescent chromogenic color-development towards efficient bright-field and photoacoustic imaging in both planar and volumetric formats, which is applicable to both cultured cells and biological tissues. Compared to the conventional ExM methods, our strategy provides an expanded toolkit, which we term as expansion fluorescence and photoacoustic microscopy (ExFLPAM), by allowing on-demand fluorescent protein labeling of cultured cells, as well as non-fluorescent absorption contrast-imaging of biological samples.

Abstract We describe in this work an evaluation of bundles of hollow mesoporous silicon nanotubes to facilitate transfection of HeLa cells using small interfering RNA designed to knock down expression of Enhanced Green Fluorescent Protein (eGFP). These experiments entail direct visualization of the nanotube bundles associated with the cells using both scanning electron microscopy (SEM) and confocal fluorescence imaging. These nanotube bundles are generated by surface modification of nanotube arrays with aminopropyl‐triethoxysilane (APTES), followed by their ultrasonication in water, to create the amine‐terminated structures capable of electrostatic conjugation of siRNA at an efficiency of 23%–50% (depending on initial siRNA concentration). Delivery and transfection to HeLa cells are verified by quantification of fluorescence imaging; an average percent knockdown of ∼50% eGFP is achieved. As nanoscale drug delivery vehicles are expected to be resorbed in clinical use, we also assess SiNT bundle degradation during the above in vitro timescale using scanning and transmission electron (TEM) microscopies. We conclude with a brief discussion of challenges and opportunities in future experiments involving this platform.

Functional gene and protein characterizations in parasitic protists are often limited by their genetic tractability. Despite the development of CRISPR-Cas9-derived or inspired approaches for a handful of protist parasites, the overall genetic tractability of these organisms remains limited. The intestinal parasite Giardia lamblia is one such species, with the added challenge of a paucity of reliable selection markers.To address this limitation, we tested the feasibility of using Nourseothricin as an effective selection agent in Giardia. Here, we report that axenically-grown WB Giardia cells are sensitive to Nourseothricin and that engineering expression of the streptothricin acetyltransferase (SAT-1) gene from Streptomyces rochei in transgenic parasites confers resistance to this antibiotic. Furthermore, we determine that SAT-1-expressing parasites are cross-resistant neither to Neomycin nor Puromycin, which are widely used to select for transgenic parasites. Consequently, we show that Nourseothricin can be used in sequential combination with both Neomycin and Puromycin to select for dual transfection events.This work increases the number of reliable selection agents and markers for Giardia genetic manipulation, expanding the limited molecular toolbox for this species of global medical importance.

Large serine recombinases (LSRs) are DNA integrases that facilitate the site-specific integration of mobile genetic elements into bacterial genomes. Only a few LSRs, such as Bxb1 and PhiC31, have been characterized to date, with limited efficiency as tools for DNA integration in human cells. In this study, we developed a computational approach to identify thousands of LSRs and their DNA attachment sites, expanding known LSR diversity by >100-fold and enabling the prediction of their insertion site specificities. We tested their recombination activity in human cells, classifying them as landing pad, genome-targeting or multi-targeting LSRs. Overall, we achieved up to seven-fold higher recombination than Bxb1 and genome integration efficiencies of 40-75% with cargo sizes over 7 kb. We also demonstrate virus-free, direct integration of plasmid or amplicon libraries for improved functional genomics applications. This systematic discovery of recombinases directly from microbial sequencing data provides a resource of over 60 LSRs experimentally characterized in human cells for large-payload genome insertion without exposed DNA double-stranded breaks.

Objective To investigate the method for establishing an immortalized mouse corneal epithelial cell line, and to identify the stability of its phenotype. Methods Primary mouse corneal epithelial cells were extracted and transfected with Simian Vacuolating Virus 40 Large T Antigen (SV40-LT) lentivirus to establish an immortalized cell line. HE staining and immunofluorescent staining were used to identify the phenotypes and markers (K12, Pax6, Ki-67) of corneal epithelium. Primary cor-neal epithelial cells were extracted to identify K14 protein in corneal epithelial cell layer, and bright field observation was performed to evaluate cell morphological characteristics. Several markers (K12, Pax6, Ki-67, ABCG2, K14) were identified for P1 and P8 cells after transfection. Crystal violet staining was used to observe the colony-formation ability of P1 and P8 cells after transfection. Results Mouse corneal epithelium was stained positive for K12, Pax6 and Ki-67, while the P1 and P8 generations of mouse cor-neal epithelial cells were stained positive for K12, Pax6, Ki-67, K14, and ABCG2; there were no significant differences in the positive rates of the above markers (P>0.05). There was no significant difference in colony-formation ability between P1 and P8 cells (P>0.05). Conclusion The immortalized mouse corneal epithelial cell line is successfully established by transfection with SV40-LT lentivirus, which has stable phenotype and proliferation.

Abstract Background Cytotoxic T lymphocytes (CTLs) are central players in the adaptive immune response. Their functional characterization and clinical research depend on efficient and reliable transfection. Although various methods have been utilized, electroporation remains the preferred technique for transient gene over-expression. However, the efficiency of electroporation is reduced for human and mouse primary CTLs. Lonza offers kits that effectively improve plasmid DNA transfection quality. Unfortunately, the removal of key components of the cell recovery medium considerably reduced the efficiency of their kit for CTLs. Our aim was to develop a new recovery medium to be used with Lonza’s Nucleofector system that would significantly enhance transfection rates. Results We assessed the impact of different media in which the primary CTLs were placed to recover after electroporation on cell survival, transfection rate and their ability to form an immunological synapse and to perform exocytosis. We transfected the cells with pmax-GFP and large constructs encoding for either CD81-super ecliptic pHluorin or granzyme B-pHuji. The comparison of five different media for mouse and two for human CTLs demonstrated that our new recovery medium composed of Opti-MEM-GlutaMAX supplemented with HEPES, DMSO and sodium pyruvate gave the best result in cell survival (> 50%) and transfection rate (> 30 and 20% for mouse and human cells, respectively). More importantly, the functionality of CTLs was at least twice as high as with the original Lonza recovery medium. In addition, our RM significantly improved transfection efficacy of natural killer cells that are notoriously hard to electroporate. Conclusion Our results show that successful transfection depends not only on the electroporation medium and pulse sequence but also on the medium applied for cell recovery. In addition, we have reduced our reliance on proprietary products by designing an effective recovery medium for both mouse and human primary CTLs and other lymphocytes that can be easily implemented by any laboratory. We expect that this recovery medium will have a significant impact on both fundamental and applied research in immunology.

Objective(s): Zirconium-based metal-organic frameworks (MOFs) nanostructures, due to their capability of easy surface modification, are considered interesting structures for delivery. In the present study, the surfaces of UIO-66 and NH2-UIO-66 MOFs were modified by polyethyleneimine (PEI) 10000 Da, and their efficiency for plasmid delivery was evaluated. Materials and Methods: Two different approaches, were employed to prepare surface-modified nanoparticles. The physicochemical characteristics of the resulting nanoparticles, as well as their transfection efficiency and cytotoxicity, were investigated on the A549 cell line. Results: The sizes of DNA/nanocarriers for PEI-modified UIO-66 (PEI-UIO-66) were between 212–291 nm and 267–321 nm for PEI 6-bromohexanoic acid linked UIO-66 (PEI-HEX-UIO-66). The zeta potential of all was positive with the ranges of +16 to +20 mV and +23 to +26 mV for PEI-UIO-66 and PEI-HEX-UIO-66, respectively. Cellular assay results showed that the PEI linking method had a higher rate of gene transfection efficiency with minimal cytotoxicity than the wet impregnation method. The difference between transfection of modified nanoparticles compared to the PEI 10 kDa was not significant but the PEI-HEX-UIO-66 showed less cytotoxicity. Conclusion: The present study suggested that the post-synthetic modification of MOFs with PEI 10000 Da through EDC/NHS+6-bromohexanoic acid reaction can be considered as an effective approach for modifying MOFs’ structure in order to obtain nanoparticles with better biological function in the gene delivery process.

Nucleic acid-based therapeutics are a common approach that is increasingly popular for a wide spectrum of diseases. Lipid nanoparticles (LNPs) are promising delivery carriers that provide RNA stability, with strong transfection efficiency, favorable and tailorable pharmacokinetics, limited toxicity, and established translatability. In this review article, we describe the lipid-based delivery systems, focusing on lipid nanoparticles, the need of their use, provide a comprehensive analysis of each component, and highlight the advantages and disadvantages of the existing manufacturing processes. We further summarize the ongoing and completed clinical trials utilizing LNPs, indicating important aspects/questions worth of investigation, and analyze the future perspectives of this significant and promising therapeutic approach.

Introduction: Impaired fracture healing, specifically non-union, has been found to occur up to 14% in tibial shaft fractures. The current standard of care to treat non-union often requires additional surgeries which can result in long recovery times. Injectable-based therapies to accelerate fracture healing have the potential to mitigate the need for additional surgeries. Gene therapies have recently undergone significant advancements due to developments in nanotechnology, which improve mRNA stability while reducing immunogenicity. Methods: In this study, we tested the efficacy of mineral coated microparticles (MCM) and fluoride-doped MCM (FMCM) to effectively deliver firefly luciferase (FLuc) mRNA lipoplexes (LPX) to the fracture site. Here, adult mice underwent a tibia fracture and stabilization method and all treatments were locally injected into the fracture. Level of osteogenesis and amount of bone formation were assessed using gene expression and histomorphometry respectively. Localized and systemic inflammation were measured through gene expression, histopathology scoring and measuring C-reactive protein (CRP) in the serum. Lastly, daily IVIS images were taken to track and measure transfection over time. Results: MCM-LPX-FLuc and FMCM-LPX-FLuc were not found to cause any cytotoxic effects when tested in vitro. When measuring the osteogenic potential of each mineral composition, FMCM-LPX-FLuc trended higher in osteogenic markers through qRT-PCR than the other groups tested in a murine fracture and stabilization model. Despite FMCM-LPX-FLuc showing slightly elevated il-1β and il-4 levels in the fracture callus, inflammation scoring of the fracture callus did not result in any differences. Additionally, an acute systemic inflammatory response was not observed in any of the samples tested. The concentration of MCM-LPX-FLuc and FMCM-LPX-FLuc that was used in the murine fracture model did not stimulate bone when analyzed through stereological principles. Transfection efficacy and kinetics of delivery platforms revealed that FMCM-LPX-FLuc prolongs the luciferase signal both in vitro and in vivo. Discussion: These data together reveal that FMCM-LPX-FLuc could serve as a promising mRNA delivery platform for fracture healing applications.

BackgroundGlioblastoma is one of the most devastating cancer worldwide based on its locally aggressive behavior and because it cannot be cured by current therapies. Defects in alternative splicing process are frequent in cancer. Recently, we demonstrated that dysregulation of the spliceosome is directly associated with glioma development, progression, and aggressiveness.MethodsDifferent human cohorts and a dataset from different glioma mouse models were analyzed to determine the mutation frequency as well as the gene and protein expression levels between tumor and control samples of the splicing-factor-3B-subunit-1 (SF3B1), an essential and druggable spliceosome component. SF3B1 expression was also explored at the single-cell level across all cell subpopulations and transcriptomic programs. The association of SF3B1 expression with relevant clinical data (e.g., overall survival) in different human cohorts was also analyzed. Different functional (proliferation/migration/tumorspheres and colonies formation/VEGF secretion/apoptosis) and mechanistic (gene expression/signaling pathways) assays were performed in three different glioblastomas cell models (human primary cultures and cell lines) in response to SF3B1 blockade (using pladienolide B treatment). Moreover, tumor progression and formation were monitored in response to SF3B1 blockade in two preclinical xenograft glioblastoma mouse models.ResultsOur data provide novel evidence demonstrating that the splicing-factor-3B-subunit-1 (SF3B1, an essential and druggable spliceosome component) is low-frequency mutated in human gliomas (~ 1 %) but widely overexpressed in glioblastoma compared with control samples from the different human cohorts and mouse models included in the present study, wherein SF3B1 levels are associated with key molecular and clinical features (e.g., overall survival, poor prognosis and/or drug resistance). Remarkably, in vitro and in vivo blockade of SF3B1 activity with pladienolide B drastically altered multiple glioblastoma pathophysiological processes (i.e., reduction in proliferation, migration, tumorspheres formation, VEGF secretion, tumor initiation and increased apoptosis) likely by suppressing AKT/mTOR/ß-catenin pathways, and an imbalance of BCL2L1 splicing.ConclusionsTogether, we highlight SF3B1 as a potential diagnostic and prognostic biomarker and an efficient pharmacological target in glioblastoma, offering a clinically relevant opportunity worth to be explored in humans.

Messenger RNA (mRNA) is the molecule which carries genetic information from DNA and guides the synthesis of protein. It participates in many cellular cascades and exhibits substantial associations with certain diseases. The development of advanced approaches for mRNA sensing and imaging is of utmost importance for biological studies and early clinical diagnosis. Herein, a novel fluorescent method is demonstrated for highly sensitive analysis of mRNA based on entropy‐driven strand displacements around three‐dimensional DNA nanostructures. Tetrahedral DNA with four pendant linear sequences provides excellent molecular scaffold loading at multiple sites for target mRNA‐initiated cascade toehold strand displacement reactions. The variations of fluorescence resonance energy transfer states can be used to indicate the presence and level of target mRNA. Besides, MnO2 nanosheets are introduced for intracellular transportation of the reaction system for bioimaging. The operation is relatively simple and the developed approach provides a promising tool for mRNA‐related biological researches and clinical applications. [ABSTRACT FROM AUTHOR]

Transfection agents play a crucial role in facilitating the uptake of nucleic acids into eukaryotic cells offering potential therapeutic solutions for genetic disorders. However, progress in this field needs the development of improved systems that guarantee efficient transfection. Here, we describe the synthesis of a set of chemical delivery agents (TRIFAPYs) containing alkyl chains of different lengths based on the 1,3,5-tris[(4-alkyloxy-1pyridinio)methyl]benzene tribromide structure. Their delivery properties for therapeutic oligonucleotides were evaluated using PolyPurine Reverse Hoogsteen hairpins (PPRHs) as a silencing tool. The binding of liposomes to PPRHs was evaluated by retardation assays in agarose gels. The complexes had a size of 125 nm as determined by DLS, forming well-defined concentrical vesicles as visualized by Cryo-TEM. The prostate cancer cell line PC-3 was used to study the internalization of the nanoparticles by fluorescence microscopy and flow cytometry. The mechanism of entrance involved in the cellular uptake was mainly by clathrin-mediated endocytosis. Cytotoxicity analyses determined the intrinsic toxicity caused by each TRIFAPY and the effect on cell viability upon transfection of a specific PPRH (HpsPr-C) directed against the antiapoptotic target survivin. TRIFAPYs C12-C18 were selected to expand these studies in the breast cancer cell line SKBR-3 opening the usage of TRIFAPYs for both sexes and, in the hCMEC/D3 cell line, as a model for the blood–brain barrier. The mRNA levels of survivin decreased, while apoptosis levels increased upon the transfection of HpsPr-C with these TRIFAPYs in PC-3 cells. Therefore, TRIFAPYs can be considered novel lipid-based vehicles for the delivery of therapeutic oligonucleotides. [ABSTRACT FROM AUTHOR]

Chromosome conformation capture techniques have revolutionized our understanding of chromatin architecture and dynamics at the genome-wide scale. In recent years, these methods have been applied to a diverse array of species, revealing fundamental principles of chromosomal organization. However, structural organization of the extrachromosomal entities, like viral genomes or plasmids, and their interactions with the host genome, remain relatively underexplored. In this work, we introduce an enhanced 4C-protocol tailored for probing plasmid DNA interactions. We design specific plasmid vector and optimize protocol to allow high detection rate of contacts between the plasmid and host DNA. [ABSTRACT FROM AUTHOR]

A 2-stage method of chitosan modification providing controlled addition of the quaternized block has been proposed. The structure of the products obtained was studied by FT-IR and NMR spectroscopy; their solubility and acid-base properties was characterized by turbodimetry and potentiometry, respectively. The presence about 50% of quaternized amino groups was shown to be necessary to obtain soluble products. The difference in pH-sensitivity of modified derivatives with different types of quaternized block attachment was revealed by studying their interaction with a model polystyrene sulfonate anion. The possibility of preparing complexes based on the obtained derivatives with DNA, polyplexes, stable under conditions close to physiological ones has been demonstrated. It is shown that the presence of primary amino groups on the polycation chains leads to a decrease in the polyplexe size. The data we obtained can form the basis for development of drug and genetic material delivery systems. [ABSTRACT FROM AUTHOR]

Electroporation (EP) stands out as a promising non-viral plasmid delivery strategy, although achieving optimal transfection efficiency in vivo remains a challenge. A noteworthy advancement in the field of in vivo EP is the application of hyaluronidase, an enzyme with the capacity to degrade hyaluronic acid in the extracellular matrix, which thereby enhances DNA transfer efficiency by 2- to 3-fold. This paper focuses on elucidating the mechanism of hyaluronidase's impact on transfection efficiency. We demonstrate that hyaluronidase promotes a more uniform distribution of plasmid DNA (pDNA) within skeletal muscle. Additionally, our study investigates the effect of the timing of hyaluronidase pretreatment on EP efficiency by including time intervals of 0, 5, and 30 min between hyaluronidase treatment and the application of pulses. Serum levels of the pDNA-encoded transgene reveal a minimal influence of the hyaluronidase pretreatment time on the final serum protein levels following delivery in both mice and rabbit models. Leveraging bioimpedance measurements, we capture morphological changes in muscle induced by hyaluronidase treatment, which result in a varied pDNA distribution. Subsequently, these findings are employed to optimize EP electrical parameters following hyaluronidase treatment in animal models. This paper offers novel insights into the potential of hyaluronidase in enhancing the effectiveness of in vivo EP, as well as guides optimized electroporation strategies following hyaluronidase use. [ABSTRACT FROM AUTHOR]

Background: Cytotoxic T lymphocytes (CTLs) are central players in the adaptive immune response. Their functional characterization and clinical research depend on efficient and reliable transfection. Although various methods have been utilized, electroporation remains the preferred technique for transient gene over-expression. However, the efficiency of electroporation is reduced for human and mouse primary CTLs. Lonza offers kits that effectively improve plasmid DNA transfection quality. Unfortunately, the removal of key components of the cell recovery medium considerably reduced the efficiency of their kit for CTLs. Our aim was to develop a new recovery medium to be used with Lonza's Nucleofector system that would significantly enhance transfection rates. Results: We assessed the impact of different media in which the primary CTLs were placed to recover after electroporation on cell survival, transfection rate and their ability to form an immunological synapse and to perform exocytosis. We transfected the cells with pmax-GFP and large constructs encoding for either CD81-super ecliptic pHluorin or granzyme B-pHuji. The comparison of five different media for mouse and two for human CTLs demonstrated that our new recovery medium composed of Opti-MEM-GlutaMAX supplemented with HEPES, DMSO and sodium pyruvate gave the best result in cell survival (> 50%) and transfection rate (> 30 and 20% for mouse and human cells, respectively). More importantly, the functionality of CTLs was at least twice as high as with the original Lonza recovery medium. In addition, our RM significantly improved transfection efficacy of natural killer cells that are notoriously hard to electroporate. Conclusion: Our results show that successful transfection depends not only on the electroporation medium and pulse sequence but also on the medium applied for cell recovery. In addition, we have reduced our reliance on proprietary products by designing an effective recovery medium for both mouse and human primary CTLs and other lymphocytes that can be easily implemented by any laboratory. We expect that this recovery medium will have a significant impact on both fundamental and applied research in immunology. [ABSTRACT FROM AUTHOR]

Stimulus‐responsive large‐scale cell culture microcarriers are promising biological materials for large‐scale cell production. Herein, multifunctional thermal and magnetic microcarriers (TMMs) made of poly(N‐isopropylacrylamide) (PNIPAM), polylysines (PLLs), gelatin methacryloyl (GelMA), poly(ethylene glycol) diacrylate (PEGDA), N,N‐methylenebis(acrylamide) (MBA), Fe3O4 and SiO2 are prepared to achieve large‐scale enzyme‐free cell harvesting and also can be used as cells stereogrowth scaffold to mimic cells suspension state to develop novel application, such as recombinant proteins produced. In TMMs, NIPAM and other materials are mixed and then underwent in situ radical polymerization by UV irradition with 2‐hydroxy‐2‐methylpropiophenone as initiator, in which GelMA provides cell adhesion sites and PLLs enable a positive microenvironment with SiO2 as filler. As enzyme‐free cell microcarriers, cell harvesting from TMMs by PNIPAM are achieved at 25 °C through vortex oscillation within 15 min and TMMs can be recycled at least for four times by magnetic recovery. Moreover, TMMs can be used as stereoculture scaffold to let cells in suspension as adherent state to improve gene transfection efficiency. Combined with magnetothermal effect, TMMs can further improve gene transfer to obtain industrialization of proteins expression. Therefore, TMMs are potential for the development of cell manufacturing and the expansion of cell stereogrowth application for recombinant proteins production. [ABSTRACT FROM AUTHOR]

Bone Morphogenetic Protein 2 (BMP2), a member of the Transforming Growth Factor‐β (TGF‐β) super family of proteins and is instrumental in the repair of fractures. The synthesis of BMP2 involves extensive post‐translational processing and several studies have demonstrated the abysmally low production of rhBMP2 in eukaryotic systems, which may be due to the short half‐life of the bioactive protein. Consequently, production costs of rhBMP2 are quite high, limiting its availability to the general populace. Therefore, there is an urgent need to identify better in‐vitro systems for large scale production of rhBMP2. In the present study, we have carried out a comparative analysis of rhBMP2 production by the conventionally used Chinese Hamster ovarian cells (CHO) and goat mammary epithelial cells (GMEC), upon transfection with appropriate construct. Udder gland cells are highly secretory, and we reasoned that such cells may serve as a better in‐vitro model for large scale production of rhBMP2. Our results indicated that the synthesis and secretion of bioactive rhBMP2 by goat mammary epithelial cells was significantly higher as compared to that by CHO‐K1 cells. Our results provide strong evidence that GMECs may serve as a better alternative to other mammalian cells used for therapeutic protein production. Significance statement: The present study demonstrates the suitability of primary goat mammary epithelial cells as a system for large scale production of therapeutic proteins in‐vitro. The cells of the mammary gland are highly secretory, and we reasoned that such cells may be useful for in‐vitro production of tough‐to‐produce therapeutics like human Bone Morphogenetic protein 2 (BMP2). We demonstrate that GMECs are a better alternative to the conventionally used CHO‐K1 cells for rhBMP‐2 production. Our results provide a strong case for developing and using GMECs as an alternative system for therapeutic protein expression. [ABSTRACT FROM AUTHOR]

(1) Recombinant protein production in mammalian cells is either based on transient transfection processes, often inefficient and underlying high batch-to-batch variability, or on laborious generation of stable cell lines. Alternatively, BacMam, a transduction process using the baculovirus, can be employed. (2) Six transfecting agents were compared to baculovirus transduction in terms of transient and stable protein expression characteristics of the model protein ACE2-eGFP using HEK293-6E, CHO-K1, and Vero cell lines. Furthermore, process optimization such as expression enhancement using sodium butyrate and TSA or baculovirus purification was assessed. (3) Baculovirus transduction efficiency was superior to all transfection agents for all cell lines. Transduced protein expression was moderate, but an 18-fold expression increase was achieved using the enhancer sodium butyrate. Ultracentrifugation of baculovirus from a 3.5 L bioreactor significantly improved the transduction efficiency and protein expression. Stable cell lines were obtained with each baculovirus transduction, yet stable cell line generation after transfection was highly unreliable. (4) This study demonstrated the superiority of the BacMam platform to standard transfections. The baculovirus efficiently transduced an array of cell lines both transiently and stably and achieved the highest efficiency for all tested cell lines. The feasibility of the scale-up of baculovirus production was demonstrated and the possibility of baculovirus purification was successfully explored. [ABSTRACT FROM AUTHOR]

Although the collagenase enzyme activity of matrix metalloproteinase-9 (MMP9) is well-documented, its non-enzymatic functions remain less understood. The interaction between intracellular superoxide dismutase-1 (SOD1) and MMP9 is known, with SOD1 suppressing MMP9. However, the mechanism by which MMP9, a secretory protein, influences the extracellular antioxidant superoxide dismutase-3 (SOD3) is not yet clear. To explore MMP9's regulatory impact on SOD3, we employed human embryonic kidney-293 cells, transfecting them with MMP9 overexpresssion and catalytic-site mutant plasmids. Additionally, MMP9 overexpressing cells were treated with an MMP9 activator and inhibitor. Analyses of both cell lysates and culture medium provided insights into MMP9's intracellular and extracellular regulatory roles. In-silico analysis and experimental approaches like proximal ligation assay and co-immunoprecipitation were utilized to delineate the protein-protein interactions between MMP9 and SOD3. Our findings indicate that activated MMP9 enhances SOD3 levels, a regulation not hindered by MMP9 inhibitors. Intriguingly, catalytically inactive MMP9 appeared to reduce SOD3 levels, likely due to MMP9's binding with SOD3, leading to their proteolytic degradation. This MMP9 influence on SOD3 was consistent in both intracellular and extracellular environments, suggesting a parallel in MMP9-SOD3 interactions across these domains. Ultimately, this study unveils a novel interaction between MMP9 and SOD3, highlighting the unique regulatory role of catalytically inactive MMP9 in diminishing SOD3 levels, contrasting its usual upregulation by active MMP9. [ABSTRACT FROM AUTHOR]

Non-viral vectors have been developing in gene delivery due to their safety and low immunogenicity. But their transfection effect is usually very low, thus limiting the application. Hence, we designed eight peptides (compounds 1–8). We compared their performances; compound 8 had the best transfection efficacy and biocompatibility. The transfection effect was similar with that of PEI, a most-widely-employed commercial transfection reagent. Atomic force microscope (AFM) images showed that the compound could self-assemble and the self-assembled peptide might encapsulate DNA. Based on these results, we further analyzed the inhibitory result in cancer cells and found that compound 8 could partially fight against Hela cells. Therefore, the compound is promising to pave the way for the development of more effective and less toxic transfection vectors. [ABSTRACT FROM AUTHOR]